Ostomy bags are in widespread use for collecting unabsorbed or excreted bodily waste material from the digestive tracts of colostomy, ileostomy and urostomy patients. Disposal of used ostomy bags and their contents presents a serious practical problem for users. This has led to various proposals for ostomy bags that can be disposed of (with contents) by being flushed down a conventional domestic water closet (WC). Potential problems that arise in this connection include bags floating and failing to flush and bags flushing but causing blockage of drains. Flushable ostomy bags should also ideally be biodegradable, for environmental reasons.
GB 2083762 discloses a WC-disposable ostomy pouch made of composite sheet material comprising an inner layer of mechanically weaker, water-impermeable material, e.g. polyvinylidene chloride (PVDC) and an outer layer of mechanically stronger, water-soluble or disintegratable material, e.g. appropriate grades of polyvinyl alcohol (PVA).
WO 94/12128 discloses an ostomy bag comprising a water-impermeable outer bag, e.g. of polyvinyl chloride (PVC) and a water impermeable inner bag, e.g. of polyvinyl alcohol (PVA) of a grade that is slowly soluble in cold water. The outer and inner bags are detachably secured together such that when the bag has been used and is ready for disposal, the outer bag is detached from the inner bag for separate disposal, e.g. in a domestic household waste bin. The inner bag and contents are removed from the body of a user and can be flushed away down a WC.
Another approach is to provide flushable ostomy bags comprising pH-sensitive material. See, e.g., GB 2195919 and U.S. Pat. No. 5,417,677.
WO 96/37171 discloses other approaches including flushable ostomy pouches comprising water-insoluble but organic solvent-soluble materials.